It is standard practice to form wire or rod into coils so that it can be handled conveniently. This coiling is normally done at the downstream end of a rolling or drawing line of a wire or rod mill. To this end the wire, which is delivered in a straight horizontal line, is normally bent gently through 90.degree. so that it moves continuously downward along a vertical axis toward the location where it is to be formed into a coil.
A delivery pipe is provided which is generally spiral shaped and which has an upper inlet end opening along this vertical axis and receiving the wire and a lower outlet end which opens generally tangentially of a circle lying in a plane perpendicular to the vertical axis. This entire pipe is rotated about the vertical axis so its outlet end moves at a peripheral speed equal to the speed at which the wire is delivered. Thus the arrangement is capable of forming a stack of coils constituting a very neat bundle.
It has been suggested in German application 2,039,572 published 17 Feb. 1972 to reduce wear of this pipe by providing it with a succession of so-called roller stars alternating with annular guide collars. Each roller star has three rollers each lying in a respective plane including the respective portion of the guide path along which the wire or rod passes in the pipe, the planes being angularly equispaced at 120.degree.. All of the rotation axes of the rollers of each star lie in a respective plane perpendicular to the path at the respective location.
This arrangement does indeed considerably reduce wear, but is quite complex and, hence, rather expensive. It is usually necessary to completely disassemble the delivery arm if a single roller or its bearing wears out. Furthermore the guide collars provided between the stars are subject to considerable wear.